Improvement in process of electroplating iron and other metals with copper



J. E. WALGOTT. ELEOTROPLATING IRON WITH COPPER.

No. 34,470. Patented Feb. 18, 1862.

Wi'naww: [72067242 04 1- %/a %M% EWMM v UNITED STATES PATENT OFFICE.

JABEZ E. WALOOTT, OF BOSTON, MASSAOHUSETTS, AS SIGNOR TO WILLIAM HOOPERBLAOKLER, OF SAME PLACE.

IMPROVEMENT lN PROCESS OF ELECTROPLAIlNG IRON AND OTHER METALSWITH'COPPER.

Specification forming part of Letters Patent No. 34,470, dated February18, 1862.

To all whom it may concern Be it known that I, JABEZ E. WALGOTT, ofBoston, in the county of Suffolk and State of Massachusetts, hay einvented a new and Improved Process of ltlectroplatin g with Copper, ofwhich the following is a full, clear, and exact description, referencebeing had to the aceompan yin g drawing, making part of thisspecification, in which is represented the apparatus which I employ incarrying out my invention.

Where sulphate of copper is employed for the purpose of electroplatingwith copper, if the metal (iron for example) be soluble in sulphuricacid .it will be corroded by the acid and the copper will not adhere toit; but even with metals that are not liable to be corroded by the acidthe process is an exceedingly slow one, and in consequence veryexpensive.

For the purpose of plating iron with copper in order to secure theadhesion of the two metals and to prevent the corrosion of the iron, ithas heretofore been necessary to employ a solution composed of a mixtureof cyanide copper and cyanide of pot-assa; but this process is withoutany practical utility in the arts, first, on account ofits great expensesecondly, on account of the poisonous fumes which are given off while itis going on, and which are very deleterious to the health of theoperatives. A process, therefore, by which copper may be deposited uponand made to adhere to the surface of iron and other metals soluble insulphuric acid without the use of sulphate or of cyanide of copper, andwhich shall be less expensive than where either of these substances isused, and also free from the poisonous effects before spoken of, is agreat desideratuin in the arts. This desideratum is attained and thebefore-mentioned inconveniences, as well as the great expense heretoforeincurred, are avoided by my improved process, which I will now proceedmore particularly todescribe.

Iam aware that a weak solution of cyanide of potassa in water, inconnection with a galvanic current, has been employed for the purpose ofplating with silver and some of the other metals 3 but such process hasproved en'- tirely inapplicable and unavailing for the purpose ofplating iron with copper. In the course of extensive experiments I havediscovered that by th'eemployment of a solution of fused cyanide ofp'otassa of great 'stren gth in connection with a powerful galvanic.

current I am enabled to plate iron and other metals rapidly andeconomically with copper without the employment of either sulphate orcyanide of copper and without danger or ineonvenienceto the workmen.

To enable others skilled in the art to understand my improved process, Iwill proceed to describe the mannerinwhich I have carried it out.

In the accompanying drawing, A is a vessel of glass or of any othersuitable material which will not suli'erdecomposition when'brought incontact with the agents employed and will permit the contained solution.to be warmed. This vessel I partially fill with a strong solution ofcyanide of potassa, two pounds or there about being dissolved in onegallon of water, the temperature of the solution being raised to about150 Fahrenheit. Into this bath I .introduce the two poles-of a galvanicbattery of sufficient strength to do the work. As this depends in ameasure on the size of the bath and of the articles to be plated, nodefinite rule as to the strength of thecurrent can be given-for allcases; but a very strong current being required I use a Bunsen battery,as representedin the drawing, in which B is a glass vessel containingsulphuric acid and water; 0, the zinc to which isattached a copper wire,b. Within the zinc cylinder 0 is placed the porous cup D, which ispartially filled with nitric acid,- and into which is introduced ablock, E, of carbon. To this block is connected another copper wire, f,to which is attached a large plate of copper, g, (the anode,) and to thewire b is attached the iron cathode'lt. The battery now being inoperation, the copper plate g and the iron plate h are both insertedinto the bath in the vessel A, when, by the action of the galvaniccurrent, the copper of the plate 9 is dissolved off. This action ispermitted to go on until the solution in the vessel A is sufficientlysaturated with copper, which will be indicated bya good deposit ofcopper on the iron plate h. The ar ticle to be plated is now introducedinto the bath A in contact with the pole b of the battery, when thecopper is deposited upon it, the

supply of copper being" kept up in the bath by 7 being dissolved 01ffrom the plate g. The operation may thus be continued uninterruptedlyuntil the article being operated upon has been plated to the requiredthickness with copper.

The strength of the current required to commeuce the deposition of thecopper upon the iron will depend upon the amount of surface to becoated. In general four Bunsen cups of one pint capacity are required tocommence the deposition of the copper upon a surface of one square footof iron. After the iron is once coated with copper and the depositionbecomes one of copper upon copper it is simply necessary that-thesurface of zinc in the battery be about equal to the surface on whichthe deposit is being made. Were a less-powerful current employed at thecommencement of theoperation the copper which would be deposited wouldnot adhere to the iron.

The important result which I have attained consists in the fact that thecopper deposited by my process adheres as firmly to the iron as in anyof the previously-known processes, while the cost of theoperation is soreduced and the operation is so divested of any deleterious effects uponthe workmen that it can be madeof practical value in the arts.

W This process may be employed in depositing copper upon othersubstances than iron, but is particularly advantageous and economical inplating iron with copper.

What I claim as my invention, and desire to secure by Letters Patent,is-

The above-described process of electroplating with copper, substantiallyas described.

J. E. W'ALGOTT.

Witnesses: v

'lnos, R. ROAGH, EDMUND MASSON.

